Electric time switch



Dec. 9, 1941. J. H. HENDRIX 2,265,368

ELECTRIC TIME SWITCH Filed April 23, 1940 Z'Sheets-Sheet l D. 9, 1941. J. ,HENDRIX 2,265,368

yELECTRIC"Tmvr: SWITCH Filed April 23, 1940 2 sheets-sheet 2 E rmi Patented Dec. 9, 1941 UNITED STATES PATENT GFFICE ELECTRIC TEVIE SWITCH Joel Henry Hendrix, New Castle,-Pa.

Application April 23, 1940, Serial No. 331,252

10 Claims.

'Generically this invention relates to time controlled electric switches operable to open or close an electric circuit as desired but it is more espe- `cially` directed to the type adapted to be mounted as a unit on a conventional alarm clock without in any way changing the` structural arrangement of the clock.

vOne of the principal objects of this invention is the provision of an automatic electric time .switch of the rotary type adapted to be installed onanalarm clock and adapted t operate in conjunction with the alarm mechanism without vaffecting the normal winding or unwinding oper- -ations of the mechanism and without affecting the sound of the alarm.

.An important object of this invention is the provision of a time switch of the above characiter adapted to be operated at a predetermined time by the alarm mechanism, including a sectional shaft structure for connection with the ordinary alarm winding shaft, thereby permitting use of the alarm winding key to effect windingof the alarm mechanism in its normal man- -ner without regard to the switch mechanism,

and means for mounting the switch mechanism onthe clock without deadening the sound of the :alarm and attachable by fastening means carried by theA clock without affecting their normal functioning.

Another important object of this invention is the provision ofa time controlled rotary switch of this character having settable arrestor ele- 'ments for vstopping or releasing the alarm winding means to open or close an electrical circuit to turn on or off electric lights, radios and different types of electrical appliances, and to control the starting and stopping of motors and the like, as desired.

A` still further important object of this inven- -tion is the provision of a time control switch will become apparent as the description proceeds, the invention resides in the construction, combination and arrangement of parts, hereinafter more fully described and claimed, and illustrated in the accompanying drawings, in which like characters of reference indicate like parts throughout the severalgures, of which:

Fig. 1 is an elevation of the assembly.

Fig. la is a diagrammatic View of the contacts and wiring diagram.

Fig. 2 is an yelevation ofthe switch mechanism with cover removed.

Fig. 3 is a section on line 3 3 of Fig. 2.

Fig. 4 is a .section on the line 4 4 of Fig. 2.

Fig. 5 is a section on the line 5 5 of Fig. 3.

Fig. 6 is a similar view to Fig. 5 with the stop or arrestor elements in different positions.

Fig. '7 is a section onthe line '1 1 of Fig. 2.

Fig, 8 is a detail of one of the movable arrestor elements.

Fig. 9 is a section on the line 9 9 of Fig. 2.

Fig. 10 is a view similar to Fig. 6 showing the form applicable to clocks having a left hand wind.

Fig. 11 is a view vsimilar to Fig. 9 showing a modiiiedform of arrestor and detachable handle.

Fig. l2 is a View similar to Fig. 9 showing a modified form of shaft construction.

The switch mechanisms of this general character with which I am familiar have proven deficient in many respects, such as being difcult to install, complex in construction, expensive to produce, and not adaptable to diiferent types of clocks without material change to existing structures, and it was to overcome such disadvantages and to provide a time switch simple in construction, of a size and configuration presenting a pleasing appearance and easily installable without marring the appearance of the clock,

adapted to utilize the clock alarm winding key,

vso constructed that the alarm mechanism may Vthe construction of the arrestor elements and co-acting switch mechanism being such that operation of the winding mechanism in winding With .theseand other objects in View, which direction will automatically move said elements to neutral position irrespective of their setting and which permits normal winding of the alarm mechanism without regard to the switch mechanism or position of the arrestor elements, said arrestor elements adapted to control the alarm mechanism in unwinding direction or counterclockwise to effect making or breaking of the circuit to start or stop electrical appliances, turn on or off lights, etc., according to a predetermined time setting as desired. v

In the illustrated embodiment characterizing this invention there is shown conventional alarm clock A, in the present instance of the Big Ben type, and my improved time switch mechanism B adapted to be maintained thereon in conjunction with the alarm, as clearly shown in Fig. l. In the present instance the casing I of switch B is substantially pear-shaped in conguration and is formed with an annular hollowed out portion 2 terminating in an elongated or stem portion 3, said casing being preferably Vconstructed of an insulating material. Said casing I is adapted to be suitably mounted on a base plate 4 extending beyond the edge of the casing and terminating in an extension 5 formed with a central opening B adapted to receive the clock hand winding knob 1 and is perforated to receive the three screws 8, the normal function of which is to maintain the rear face or bell portion 9 attached to the rear of the clock A. It will be understood that said clock includes the conventional winding key I and alarm winding key II as well as the alarm setting knob I2. In order to support the switch mechanism B out of contact with the rear face or bell 9 so as not t0 deaden or interfere with the sounding of the alarm, portion of base plate 4 is of a greater thickness as at I3 than the rest of the plate, or if the plate and extension are of the same thickness the extension may be formed with a plurality of lugs corresponding to the thickness I3.

The casing or housing is formed with a central opening I4 and with an integral collar or boss I5 extending above the bottom surface I6 of the casing. An annular slot I1 is formed in the inner surface of casing wall I8 adjacent bottom I6 for a purpose hereinafter more fully appearing. The stem portion 3 is formed in its end with a countersunk opening I9. A pair of contact elements 20 formed with curved portions 2I terminating at one end in straight plug portions 22 and with diametrically opposite lateral inwardly projecting contact plates 23, are embedded in the upper surface 24 of casing wall I8 with the plug ends 22 extending within opening I9 for engagement with corresponding openings in the plug-socket 25 connected to one end of electric wires 26 and 21 having their other ends connected to a suitable source of electrical energy when said plug 25 is inserted in opening I9 as clearly shown in Fig. 1.

Normally the key II is threadedly mounted on the alarm winding shaft Il. In order to utilize the key II for winding the alarm when the switch B has been positioned it is only necessary to extend or lengthen the shaft II which is accomplished by forming a shaft section 28 square in cross section with a threaded opening 29 in one end for engagement with the threaded end of said shaft II, and a shaft section 3B complementally bored as at 3| for telescopic engagement with the free squared end of section 28 and extending beyond the bottom surface of casing I, its opposite end extending through opening 32 to a point substantially flush with the outer surface of casing top 33 and terminating in a reduced threaded end post 34, corresponding to the threaded end of shaft II', and adapted to be engaged by the internally threaded shank IIa of key II thereby forming a continuation of shaft II' as will be well understood. The casing top 33 is detachably secured to casing wall I8 by the threaded screws 35. Interposed between shaft 30 and key shank IIa is a washer 36.

Integrally or otherwise mounted on shaft section 30 is an arrestor plate 31 terminating in a point 38, one edge of the plate adjacent said point being formed with a straight edge 39 and the opposite edge of the point curved as at 40, said plate 31 seating on boss I5 and end 38 adapted to travel in the slot I1 as clearly shown in Fig. 3. A perpendicular slot 4I is formed in wall I8 intersecting slot I1 to permit the insertion of end 38 in slot I1 as will hereinafter more fully appear. Mounted on the opposite end of plate 31 is an insulating block 42 on which is mounted the rotatable contact member C comprising superimposed plate members 43 separated at their opposite ends as at 44 forming a pair of end contacts 44' to engage opposite sides of the stationary diametrically opposed contact plates 23 when in bridging relation therewith and to permit passage of the plates 23 therebetween during rotary movement of said contact member C, as will be well understood. The rotary contact C is mounted on block 42 by screws 45 which do not extend beyond the lower surface of said block and which effect binding engagement of the plates 43 with each other central of their length.

The wall I8 of casing I is formed with a pair of spaced perpendicular bored openings 46 and 41 extending through and beyond slot I1 to a point 48 as clearly shown in Fig. 7. The cylindrical rotary switch arrestor elements 49 and 50 are adapted for insertion in the respective openings 46 and 41 and are formed adjacent their lower ends with crescent-like cut-out portions 5I and the off center or eccentric stop portions 52 formed with a cam surface 53. Said arrestors 49 and 50 are provided with handles 53 and 54 integrally or otherwise connected to their upper ends and extending laterally therefrom in substantial alignment with the crescent cut-out portions 5I and adapted to project through openings 55 formed in the flange 56 of top 33 and are of such a width that the end walls thereof will constitute stops for limiting the arcuate movement of the handles in both directions as will hereinafter more fully appear.

When the handles 53 and 54 are moved counter-clockwise or to the left to the limit of their movement so that the cut-out portions 5I are in alignment with and constitute continuations of slot I1, arrestor plate 31 may freely move in either clockwise or counter-clockwise directions, but when for instance, handle 54 is moved in a clockwise or right hand direction to the limit of its movement as shown in dotted line b, the eccentric stop 52 is positioned to interrupt slot I1 and operates to stop arrestor plate 31 when rotating in anti-clockwise direction and which stops the rotation of the alarm mechanism and maintains switch C in bridging alignment with stationary contacts 23 to close the electrical circuit through the switch, as will directly be described, and if handle 54 is to the left in open position and handle 53 is in its right hand posicounter-clockwise wind.

In this form thestop 52a will .be positioned tothe left and the opening will be to the right and the arrestor plate 31a will be reversed so :that the curved'edge'40 will befon the left hand ,iside and the straight edge139 will be to the right, that is, reversed as to the form shown in Figs. 5 and 6. In the form illustrated in Fig. y10 the key Il will be turned in a counter-clockwise direction to wind the alarm mechanism and to `unwind will move in a clockwise direction to engage stop :52 to arrest the movement of the rotaryswitch contact C. In both forms of the invention if it is desired that the screws 45 extend through arrestor plate 31 the same may be provided with bushings of insulating material 51 so that there will beno-short circuit of the electri-c current during the passage through the rotary switch mechanism.

It will thus beapparent that the device forming the subject matter of this invention may be lapplied to clocks having a left -hand wind by f ,simplyreversing the parts above referred to.

With further reference to the wiring diagram, `it will be noted that one end ofthe wires 26 and -21 -are connected to plug-socket 25, their other-ends connected to a male portion 58 con- -nectedto a female portion '59 of an electrical connectionrto whichis connected wires-60 and 6l of a lamp D, the wire 21 being severed intermediateits length and the severed ends 62 and 63 being connected to the plug portion V64 of a socket portion 65, said socket portion 65 being connected by wires 66 andv 61 to a source of electrical energy as at168, so that the circuit will be completed through conductor 66, socket portion'65plug 64, conductor 21, connections'58, 59, wire 66, lamp D, wire 6l, :connections 59, 58, wire 26, plug 25, contact 2|, contact plate y23,.switch C, contact plate -23, contact2l, plugsocket 25, conductor 21, connections`64, 65, and conductor 61, back'to source68.

Suitably secured to the alarm windingkey li is a pointer strip 69 positioned zin substantial alignment with the rotary switch mechanism C so that the on and off positions of :said Vswitch mechanism is indicated, said-pointer orindicator 69 co-acting with a marking 1,6 carried `by ythe upper surface of topl33 of .casing |:to.effect the initial setting ofthe switch mechanism withrelspect to the arrestors 49 and 59 so that when said rotary switch is releasedby the'alarm mechanism in accordance with a predetermined time setting, said mechanism will .be in .position to engage the respective '-'arrestors .in vaccordance with their predetermined setting to turn onor 01T lights or other applianceasdesired.

It will be noted that whilein the present-instance the device B is shown to be suitably supported on a base plate 4-terminating in an eX- tension '5 constructed with perforations .to vre- -ceive the screws l8 carriedby ari-alarm clock of .the Big Ben type,'it is `to'be understood'that plate 4 andextension 5-may be modied to adapt isapplication to other alarm clock constructions without departing from the scope and spirit of :this invention.

Velectric Vmotor,wand the like, and connect plugsocket25 with plug ends 22 of theswitch mechanism, wind the alarm mechanism by key Il, set the time alarm and arrestors 49 and -5yto respective current -on or olf positions, setthe pointer 69 in alignment with marking 10, and when the alarmmechanism is released the rotary switch mechanism C will be moved to circuit opening orclosing positions in accordance with the pre'deterrninedtimev setting.

In order to further facilitate the setting V.of the'arrestor elements 49 and-5U to effect their smooth operation irrespective of the-exact locationof the openings 46 and 41 andwhetherthe alarm wind is to the right or to the left, it-may ,be found desirable, as shown in'Fig. 11, to form said arrestors 49 and :50 adjacent their uppero-r free ends with afseries of spaced openings 1l, handle 54h being vdetachable and adapted for suitable engagement with a selected opening as desired.

Further, as illustrated in Fig. 12, if desired, shaft section 39a may be Vformed with a cylindrical .opening 12 vcommunicating with squared .bore 31a, and a Acylindrical shaft section '13 may beintegrally connected `toandform a continuation of squared shaft section 28a adapted to :extend throughand beyond opening '32a and terminate inkey portion 14. Thus'the sectionsnZBa, :'13 andportion 14 constituteva unitary key structure adapted for threaded connection with shaft H to'form a continuation thereof and wheninserted in shaft 36a form a combined unitary structure. The opening 35a is so positioned that the arrestor plate 31 extends at right angles to opposite sides-of portion 28a, so that whenthe key is inserted in opening 31a portion 14 will be in alignment with end 38 of plate 31 constituting a pointer '69a for determining and positioning said plate, similar to key Hand pointer 69, with respect to marking 10.

While the operation of the device .would seem tobe clearfrom the above description it might be well to further state that when the device isfoperatively positioned on-an alarm clock and the alarmmechanism woundwith pointer 69 in alignment with indicating marker 'f1-S, itbeing understoodrthat thealarm mechanism has been `set to operate at a predetermined time, and it is desired `that the lamp D be lighted the arrestor yhandle 54 of` arrestor is positioned to the right so that'the arrestor or Astop portion 52-wi1lbe positioned in slot I1 so that when the A-alarm mechanismand switch C is released rotary movement thereof will be arrested when plate 31 engages portion'52 and switch C will be maintained in bridging or circuit closing position with respect to stationary contacts 23 to complete the circuit through and light said lamp D as hereinbefore described.

When it is desired that the electrical circuit through lamp Dl remain closed and the light-on, the initial operation isthe-same las above Adescribed-except the-switch member C is `held yin bridging relation with contacts 23 by the alarm mechanism. Handle 54 is moved in anti-clockwise or left-hand direction to its limit of movement aligning slot 5I with slot l1 and handle 53 of arrestor 49 is moved to its limit of movement to the right so as to interrupt slot I1 by stop 52, and with this setting, when the alarm mechanism is released in accordance with the predetermined time setting effecting rotation of the rotary switch member C the circuit through said switch is broken and plate 31 passes arrestor 50 and engages stop 52 of arrestor 49 arresting the rotary movement of the alarm mechanism and switch member C and maintaining the circuit broken and lights off.

It is to be noted that the mounting of the time switch device constituting the instant invention on a conventional alarm clock does not in any way affect or interfere with the operation of the clock in its normal manner and to effect this end all that is necessary is to position the handles 53 and 54at the limit of their movement in left or anti-clockwise directions so as not to interrupt slot I1 and, when so positioned, the rotary movement of the alarm mechanism in winding and unwinding directions and the continuous or repeat sounding of the alarm may be effected as freely and completely as if the device B was not carried by or connected to the clock.

It will be especially observed that in order to prevent damage to the switch mechanism the construction of the arrestors 49 and 50 and the arrestor plate 31 is such that irrrespective of the position of the eccentric stop portions 52,

when the alarm and switch mechanism is rotated in clock winding or clockwise direction plate 31 will eilect automatic movement of arrestors 49 and 50 to neutral or non-slot interrupting positions by the engagement of the curved edge 40 with cam face 53 or the edge of portions 52 so that irrespective of the position of said arrestors the alarm mechanism may be wound the same as if the device was not installed and without any damage to the switch mechanism.

In View of the above it will be apparent that I have provided a time switch mechanism simple in construction, comprising few parts, easily installed on an 4alarm clock without change to existing structure, easily connected to electric light, radio, or other appliance to be controlled, so constructed as not to interfere with the normal winding operation of the alarm mechanism, manufacturable at a negligible cost, pleasing in appearance, and eficent for the purposes intended.

Although in practice I have found that the form of my invention illustrated in the accompanying drawings and referred to in the above description as the preferred embodiment is the most eiicient and practical, yet realizing the conditions concurrent with the adoption of my invention will necessarily vary, I desire to emphasize that various minor changes in details of construction, proportion and arrangement of parts, may be resorted to within the scope of the appended claims without departing from or sacrificing any of the principles of this invention.

Having thus described my invention, what I desire protected by Letters Patent is as set forth in the following claims:

1. An electric time switch including spaced stationary contacts, a rotary contact member adapted to be driven by a clock alarm mechanism including a pair of rotary contacts, said member being normally rotatable in an unwinding direction, arrestor elements, each of said elements having neutral and arrestor positions, one element when in neutral position adapted to permit free rotation of said rotary contact and when in the remaining position adapted to arrest the movement of the contact member with its contents in bridging relation with said stationary contacts to close an electric circuit, the other element when in neutral position permitting free rotation of said rotary member with its contacts and when in its remaining position adapted to arrest the movement of said rotary contact out of engagement with said stationary contacts to maintain the electrical circuit open, means in connection with said arrestor elements whereby rotation of the rotatable member in a winding direction automatically moves the arrestor elements to their neutral position to permit free rotation of said rotary member in either direction withoutl regard to the initial setting of said arrestor elements.

2. An electrical switch control comprising a casing, a pair of stationary contact elements carried by said casing having opposed stationary contacts adjacent one end and terminating at their free ends in plug contact members, a sectional shaft means extending through said casing, a rotary switch contact member mounted on said shaft and normally rotatable in an unwinding direction, said shaft terminating at one end in a stem, stem winding means attached to said stem, driving means for the shaft, said driving means being releasable in accordance with a predetermined time setting, arrestor means manually settable to cooperate with said rotary switch member to arrest its movement in bridging relation with said stationary contacts, and additional arrestor means manually settable for arresting movement of said switch to maintain the same in non-bridging contact, both of said arrestor means being automatically operable irrespective of their setting to permit uninterrupted rotary movement of said switch when said alarm winding shaft is rotated in alarm winding direction whereby the alarm winding mechanism may be wound in the usual manner with the winding key without regard to said electrical switch control device.

3. Switch means for controlling an electric circuit by the alarm winding shaft of a normal alarm clock, comprising a casing mounted on said clock, a winding key shaft means extending through said casing, and adapted to be connected to the alarm winding shaft so as to rotate therewith, a switch member having opposite contacts mounted on said shaft, a pair of opposed stationary contacts extending within said casing and adapted for co-action with said rotary contacts, a pair of arrestor elements carried by said casing, and an arrestor plate mounted on said shaft adapted to engage one of said elements to arres-t the rotation of said switch when in bridging relation with the stationary contacts and adapted to engage the other arrestor plate to arrest the roary movement of said switch and maintain the same in non-bridging relation with said stationary contacts, said arrestor elements being movable to positions permitting the free rotation of said arrestor and switch members in alarm winding and unwinding directions.

4. A time controlled electrical switch adapted for connection with an alarm clock including a casing, means for securing the casing to the clock spaced therefrom so as not to interfere with the normalsounding ofthealarm, an adaptorxmeans' connected with the threadedv end of the clock alarm winding shaft, a switch mechanism including a rotary member in said casing, means extending through the `casing and connecting. the rotary member with the adaptor, s-aid means proj'ecting` outwardly through the cas-ing at the other end for receiving the windinghandle normally carried by said alarm winding shaft, a pair of opposed stationary contacts carried bysaid casing for co-operation with said rotaryv contacts to make and breakan electricalcircuit through said rotary switch, an arrestor plate connected to said rotatable switch member, a'pair of arrestor elements carried by said casing and having switch arresting and neutral positions, and said switch member and arrestor plate being normally rotatable in unwinding direction, said arrestor plate engageable with one of said elements to arrest its movement when in bridging relation with said stationary contacts to close an electrical circuit therethrough and when said arrestor element is in neutral position the contact plate is adapted to engage the other element to maintain said switch in circuit opening position, said elements being movable to non-arresting positions to permit free rotation of said rotatable switch member in winding and unwinding directions.

5. Switch mechanism for controlling an electric circuit by the alarm winding shaft of a normal alarm clock, comprising a casing mounted on said clock, a shaft means extending through said casing, one end adapted for connection with the alarm winding shaft so as to rotate therewith, the other end carrying a winding key structure, a rotary switch having opposite contacts adapted to normally rotate in an unwinding direction carried by said shaft within said casing, a pair of opposed stationary contacts adapted for coaction with said rotary cont-acts, arrestor means carried by said casing, said means having arresting and neutral positions, arrestor engaging means associated with said rotary ycontact coacting with said arrestor means to arrest said rotary contact in bridging relation with said stationary contacts or in non-bridging relation depending upon the position of said arrestor means, a marking predeterminedly positioned exterior f said casing, said key structure adapted to rotate with said shaft exterior of said casing indicating the yposition of said rotary switch contact member and co-acting with said marking to effect initial setting of said rotary switch with respect to said arrestor means, characterized in that said arrestor engaging means is adapted to co-operate with said arrestor elements whereby rotation of said rotary switch member in winding direction automatically effects movement of the arrestors to their neutral positions, permitting free rotation of said alarm mechanism and switch contact member in both directions.

6. An electrical time switch including spaced stationary contacts, a rotary contact member adapted to be driven by a clock alarm mechanism and including a pair of rotary contacts, said member being normally rotatable in an unwinding direction, arrestor elements having cam stop means, means for predeterminedly setting said stop means, said latter means having stop and non-stop positions, an arrestor plate a-dapted to travel with said rotary contacts and adapted to engage one of said stop elements, when in stopping position, to arrest the rotation of said rotary contacts in bridging relation with the stationary contacts, and tosengagethe stop means of the other arrestor, when inr` stoppingV position, to: arrest. the movement' of said. switch in nonbridging relation withrespectto said stationary contacts, the stop' means of said arrestor ele.- ments being automatically movable by said arrestor plate, whenmoving. in winding` direction, to positionspermitting the free rotation of said arrestor and rotary. contacts in. alarm winding direction whereby said rotary elements may be freely rotatedin either direction.

7. A switchmeans for controlling an electric circuit bythe-alarm winding shaft of a normal alarnrclock comprising a casing. mounted on said Y clock, shaft' meansextending. through said-cas-- ing and adapted to be connected tothe alarm winding shaft so as .to rotate therewith, a switch member'` having opposite contacts mounted on said shaft means, a pair of opposed'stationary contacts extending within said casing and adapted for vco-action with said rotary contacts, a pair of settable arrestor elements carried by said casing including stop means, said means having stop and non-stop positions, an arrestor plate carried by said shaft means adapted to engage one of said stop elements, when in stopping position, to arrest the rotation of said switch in bridging relation with the stationary contacts, and adapted to engage the stop means of the other arrestor when in stopping position to arrest the rotary movement of said switch and maintain the same in non-bridging relation with said stationary contacts, the stop means of said arrestor elements by rotation of the key winding shaft in winding direction being automatically movable to positions permitting the free rotation of said arrestor and switch members in both directions, and adjustable means for Varying the setting of said stop means to permit automatic movement of said stop means by said arrestor plate in winding direction irrespective of whether the winding direction of the alarm mechanism is to the right or to the left.

8. An electrical time switch including a pair of spaced contacts, a rotary contact member adapted to be driven by the alarm mechanism of a clock in alarm winding direction and having oppositely positioned contacts, arrestor means to predeterminedly stop the movement of said contacts, said arrestor means having neutral and circuit making and breaking positions, an arrestor plate connected to said rotary member and adapted to engage said first mentioned arrestor means when in circuit making position to arrest the movement of said rotary member in bridging relation to said stationary contacts to close an electrical circuit and when in circuit breaking position adapted to arrest and maintain said contact element with the rotary contacts in circuit breaking `position to maintain the circuit open, said arrestor means being automatically moveable to neutral position by said arrestor plate upon actuation of the alarm mechanism and said rotary member in alarm winding direction.

9. In combination with an alarm clock having an alarm winding shaft projecting to the outside of the clock; of a unit fixedly maintained on said clock comprising a casing, an electrical mechanism within the casing including stationary contacts and a rotary switch structure connected to said alarm winding shaft for opening and closing an electrical circuit, said rotary structure projecting at its opposite end beyond said casing and adapted for connection with a winding key, an arrestor member Icarried by and rotatable with said rotary switch, arrestor elements carried by said casing having arresting and neutral positions and manuallyrsettable to arrest said arrestor member when moving in unwinding direction to respectively close and open said circuit as desired, said arrestor' elements being automatically operable to neutral position irrespective of their set positions by said arrestor plate upon the normal actuation of said alarm winding shaft in winding direction whereby the conventional winding of the alarm mechanism is effected without regard to said unit.

10. In combination with an alarm clock having an alarm winding shaft projecting to the outside of the clock; of a unit xedly mounted on said clock overlying said shaft comprising a casing having an annular recess, an electrical mechanism Within the casing including stationary contacts and a rotary switch structure connected to Ysaid 'alarm winding shaft for opening and closing an electrical circuit and projecting at its free end beyond said casing, an arrestor member operable in said recess and carried .by and ro tatable with said rotary switch, arrestor elements carried by said casing, said elements being manually settable to interrupt said recess and arrest said arrestor member when the latter is moving in unwinding direction to respectively close and open said circuit as desired, said arrestor elements yautomatically operable to non-recess interrupting position irrespective of their set p0- sitions by the engagement of said arrestor plate upon the normal rotation of said alarm winding shaft in Winding direction, whereby the conventional winding of the alarm winding mechanism is effected Without regard to said unit.

JOEL HENRY HENDRIX. 

